Gas furnace



J- N- ROSS GAS FURNACE July 29, 1952 3 Sheets-Sheet 1 Filed March 7, 1949 INVENTOR, BY JIW/MJ J! War-9. g/fi w,

J. N. ROSS GAS FURNACE July 29, 1952 3 Sheets-Sheet 2 Filed March 7, 1949 INVENTOR, Jz/zzar /7 Pass.

y 1952 J. N. Ross 2,604,935

GAS FURNACE Filed March 7, 1949 3 Sheets-Sheet 3 50 W mmwmmwzwmm INVENTOR, fi/mar Puss.

Patented July 29, 1952 2,604,935 1 GAS- FURNACE flames Nfl t'oss, Kansas City, Mo.. Application March 7, 1949, Serial No; sows-'1 This; invention relates to new and useful :improvements in gas furnaces, andghas particular reference to apparatus for adapting the ordinary coal burning, warmair furnace to burn, gas as a fuel. i

The principal object of the present invention is the provision of means for obtaining more efficient use of the heat produced by the burning of gas in a furnace primarily designed for the consumption of coal.

'Another object is the provision, in a furnace ofthe character described, of a gas burner adapted to direct its flame directly against the firepot, and of means for retaining heat and directing it against the walls of the firepot.

A further object is the provision, in a furnace of the character described, of acircular gas burner having substantially the same dia'n eter as the firepot so as to direct its flames directlyagainst the firepot walls, said burner being so constructed as to be passed easily through the fire door of the furnace even though said door is substantiallysmaller than the firepot.

Other objects are simplicity and economy of construction, easeand convenience of installing the burner without disassembling the furnace, and adaptability of the burner to be used in a wide variety of furnaces.

With these objects in view, as well as other objects which; will appear in the course of the specification, reference will be had to the drawing, wherein:

Figure 1 is a vertical mid-section through a furnace embodying the present invention.

Fig. 2 is a section taken on line Ill-'II of Fig. l, with parts broken away.

Fig. 3 is a perspective view of the burner'and supply pipe assembly shown apart from the furnace.

Fig. 4 is a plan view of the burner, withv parts broken away.

Fig. 5 is an .enlargedsection taken on line V--V of Fig. 4, showing a portion ofrthe-firepot and supporting disc in dotted lines.

Fig. 6 is a longitudinal section through the '1 burner pipe, taken substantially on line VI-VI of Fig. 5.

Fig. 7 is an enlarged fragmentary section taken on line VII-VII of Fig. 4.

Fig. 8 is a-perspectiveview of the burner-with a its sections relatively positioned for insertioninto the furnace.

Fig. 9 is an enlarged fragmentary section taken on line IXIX of Fig. 2.

Fig. 10 is a section taken on line XX of Fig. 9.

Like reference numerals apply to similar parts throughout the several views, and thenumeral 2 applies to a substantially circular base plate supported on the floor and having an upright peripheral flange 4 to which is secured thelower 7 ,Cla ims. (01. 158-7) edgeof a substantially cylindrical furnace casing 6. A frontplate 8 is securelyattachedv to and forms the forward wall of casingfi, and a bonnot In closes the upper end of the casing. A cold air duct I2 communicates with the lower portion vof said casing, and hot airducts l4 communicate with said casing through bonnet l0. An -ash chamber I6 is secured to base plate 2 substantially centrally within casing 6, andis provided with a forward extension, I8 which extends through front plate 8, and? is normally provided at; its outer end with a closure door. In .the present application, however, said forward exitension is sealed with a wall 20 of .firebrick through which the gas supply pi-peextends as hereinafter described. I I

Said ash chamber supports a firepot 22, said firepot supports a combustion dome '24, and: said combustion dome supports aiheat radiator 26, all in the manner of a standard coal furnace.

Combustion dome 24 is providedwith a forward tubular extension 28 through which coal is normally introduced into the firepot, said extension projecting through front plate 8 and being closed at its outer end by fire door 30. Extension 2-8 is of substantially smaller cross-sectional dimensions than firepot 22; Radiator-26 is provided with a rearward extension 32 which projects through casing 6 for connection with a suitable fiuepipe, not shown; and; a forward extension 34 which projects through front plate 8- andis normally closed at its outer end by clean-out door 36 Firepct 22 iscircular and slightly tapered; being largerat its upper end. It is provided at itslower end with an inwardly projecting annular flange 38 normally adapted to carry a-grate for supporting a firebed.

The structure so. far described isstandard' in coal fired warm air furnaces. Air entering the ash chamber passes upwardly through the firebed where it supplies oxygen for combustion. The gaseous products of combustion. then-rise through the combustion dome and pass through the radiator and out the flue connection'. Air entering casing 6 through duct. I2 is-heated by contact with the heated walls'of the firepot, combustion dome, and radiator, and flows upwardly through hot air-ducts l4.

Conversion of this type offurnace to burn gas has not been very successful, for various reasons. The passageways for the gaseous combustion products from thefir-epot to the flueare'necessarily relatively large and unrestricted in a coal furnace, since coal requires a larger-amount of air for proper burning and requires a more-pow.- erful draft. Gas is burned, and. liberates .its heat much more rapidly'with the consumption-of a much-smaller-quantity of air, and the tendency is therefore for the hot burned gases topass-so rapidly to the flue that its heat can not be -ef flames which are substantially spaced apart from..

firepot walls, which reduces the speed with which the heat of the flames is transferred from the" combustion chamber.

According to the present invention, after the grate is removed, an annular support disc 4ilis inserted into the firepct and rested on flange 38 which formerly supported the grate. Said disc is of such diameter as to fitsnugly within the lower portion of the firepot, and is provided around its inner edge with an upright flange 42. Said disc may be diametrically split as indicated at 44 in Fig. 2 to facilitate insertion of said disc through extension 28 of combustion dome 24. I

The burner 46, best shown in Figs. 3 to 8, is substantially circular, being tubular and comprising two substantially semi-circular sections 48 and 5B. Said burner is of such diameter as to rest snugly in the lower portion of the firepot, resting either on disc 40 or on the converging walls of the firepot itself. Sections 48 and 50 are connected at the rearward side of the furnace by threaded coupling 52, as best shown in Fig. 7. Section 50 is sealed at its forward end with a plug 54, and section 48 is interconnected at its forward end with a radially inwardly extending gas supply'pipe 56. Coupling 52 provides that sections 48 and 50 of the burner may be turner relatively as shown in Fig. 8 to facilitate inser tion into the furnace. When so positioned, one end section of the burner may be inserted through extension 28 of the combustion dome, and when inside it may be turned in such a manner as to permit the other end section of the burner to follow, said sections being gradually brought into coplanar relation as the second section enters the furnace. In this manner a burner having a diameter substantially equal to that of the firepot, and greater than the largest crosssectional dimension of combustion dome extension' 28, may be inserted into the furnace. After it is inserted, it is lower'ed'into' position in the firepot as previously described. It will; be noted in Fig. 7 that burner sections 48 and 50 abut firmly within coupling 52 when the sections are brought into coplanar relation. In this manner a substantially gas tight seal is obtained, although a slight leakage at this point would not be objectionable.

Burner sections 48 and 50 are provided with a series of longitudinally spaced apart holes 58 through which gas escapes and is burned. It will be noted that said holes are relatively widely spaced at the forward end of section 48, and relatively closely spaced at the forward end of section 50. This compensates for the reduction of flow pressure in the burner tube as a portion of the gas escapes at each hole, thus providing for substantially uniform consumption of gas around the burner ring, and thereby for even heating of the firepot wall. As shown in Fig. 5, holes 58 are inclined outwardly so as to direct the flames directly against the firepot, and as shown in Fig. 6 are inclined in the direction of flow of the gas as indicated by the arrow. This forward inclination of the holes provides that when gas passing through one of the holes adjacent the forward end of section 48 is ignited 4 by a suitable pilot means, not shown, the flame will ignite gas escaping from the next hole, and so on around the entire burner. 7 Gas supply pipe 56 which is connected with the burner after it is positioned in the furnace,

extends horizontally to the center of the burner,

downwardly into ash chamber 16, and horizontally forwardly through firebrick wall 20. At its outer end it is provided with a cap 60 through which an injector tube 62 extends. Said injector tube is provided at its inner end with a nozzle 64 having an orifice 66, as best shown in Figs. 9 and 10, and is connected at its outer end with gas line 68 through valve 10. Gas passing through nozzle 64 creates a suction which draws air into pipe 56 through holes 12 formed through the walls of said pipe behind the nozzle of the injector tube. The air-gas ratio depends on the ratio between the area of the annular passage 14 between pipe 56 and tube 62, and the area of orifice 66, and may be varied to provide the best possible combustion in any particular instal lation;

A hollow cylindrical wall 16 of refractory material is supported on disc 40 adjacent the inner edge thereof, being positioned by flange 42 of said disc, as best shown in Fig. 1. Said wall is comprised of longitudinal segmental sections 18 having tongue and groove joints therebetween as shown in Fig. 2, and extends upwardly to the top of firepot 22. A plurality of open-work bars of refractory material are disposed between wall 16 and the firepot walls, each of said bars resting at its lower end between burner 46 and Wall '16, and being inclined outwardly to rest at its upper end against the firepot wall substantially at the top thereof. Suflicient bars are em--' ployed to extend entirely around the firepot, as shown in Fig. 2. The space between wall 16 and bars 88 is filled with broken lumps 82 of refractory material. Flange 42 is notched as at 84, and the lower edge of wall I6 is notched as at 86, to accommodate gas supply pipe 56.

Since burner 45 directs its flames directly against the firepot walls, and since refractory wall It and bars 80 further deflect the heat outwardly against said firepot, the firepot walls are maintained at a very high temperature, which promotes a high rate of heat transfer to the 'air flowing through furnace casing 6, and consequently a more efficient use of the heat. Fur thermore, refractory members 16, 80, and 82 absorb and retain a large amount of heat until it can be transferred through the combustion chamber walls.

What I claim is: a

1. In a furnace of the class described having a circular firepot, a gas burner disposed in the lower portion of said firepot and comprising a tube of substantially circular form having an outer diameter substantially equal to that of said firepot, means for supplying gas to one end of said-burner tube, said tube having longitudinally spaced holes formed therein adapted to direct flames against the walls of said firepot, said holes being inclined upwardly and outwardly and forwardly inclined in the direction of gas flow in said burner tube, and progressively more closely spaced in the direction of gas flow.

2. For use in combination with a furnace of the class described having a combustion chamber with a firepot forming the lower portion thereof and having an access opening to said combustion chamber, the greatest dimension of said opening being smaller than the diameter of said firepot, a substantially circular gas burner comprising two substantially semi-circular sections of tubing, said burner being adapted to rest in said firepot and having an outer diameter substantially equal to the inner diameter of said firepot, and means interconnecting a pair of corresponding ends of said burner sections for relative axial oscillation, whereby said burner may be relatively positioned for insertion into the furnace through said access opening.

3. For use in combination with a furnace of the class described having a combustion chamber with a firepot forming the lower portion thereof, and having an access opening to said combustion chamber, the greatest dimension of said opening being smaller than the diameter of said firepot, a substantially circular gas burner comprising two substantially semi-circular sections of tubing, said burner being adapted to rest in said firepot and having an outer diameter substantially equal to the inner diameter of said firepot, and a threaded coupling interconnecting a pair of corresponding ends of said burner sections for relative axial oscillation, whereby said burner sections may be disposed angularly to each other for insertion into the furnace through said access opening.

4. For use in combination with a furnace of the class described having a combustion chamher with a firepot forming the lower portion thereof, and having an access opening to said combustion chamber, the greatest dimension of said opening being smaller than the diameter of said firepot, a substantially circular gas burner comprising two substantially semi-circular sections of tubing, said burner being adapted to rest in said firepot and having an outer diameter substantially eoual to the inner diameter of said firepot, and a threaded coupling interconnecting a pair of corresponding ends of said burner sections for relative axial oscillation, whereby said burner sections may be disposed angularly toeach other for insertion into the furnace through said access o ening. the ends of said burner sections normally abutting within said coupling to form a gas seal.

5. The com ination, with a furnace of the class described having an ash chamber provided with an access opening, a circular firepot havin downwardly convergent walls supported on said ash chamber and having a support flange at the lower end thereof, and a combustion dome supported on said firepot and having an access opening smaller than the minimum diameter of said firepot, of a circular gas burner carried by said support flange and comprising two substantially semi-circular tubular sections and having an outer diameter substantially equal to the minimumdiameter of said firepot, said burner being adapted to direct flames against the walls of said firepot, means connecting a corresponding pair of ends of said burner sections for relative oscillation whereby said burner may be extended for insertion into the furnace through the access opening of said combustion dome, and a gas supply pipe removably connected to the opposite end of one of said burner sections and extending into said chamber and outwardly through the access opening thereof.

"6. The combination, with a furnace of the class described having an ash chamber provided with an access opening, a circular firepot having downwardly convergent walls supported on said ash chamber and having a' support flange at the lower end thereof, and a combustion dome supported on said firepot and having an access opening smaller than the minimum diameter of said firepot, of an annular support disc carried horizontally on said support flange, a circular tubular gas burner carried on said disc and having a diameter substantially equal to the inner diameter of said firepot, said burner being adapted to direct flames against the walls of said firepot, means for supplying gas to said burner, a vertically disposed cylindrical refractory wall disposed within said burner, said wall being supported at its lower end by said disc and extending the full height of said firepot, and a plurality of refractory bars each having its lower end resting between said burner and said wall and having its upper end resting against the firepot wall.

7. The combination, with a furnace of the class described having an ash chamber provided with an access opening, a circular firepot having downwardly convergent walls supported on said ash chamber and having a support flange at the lower end thereof, and a combustion dome supported on said firepot and having an access opening smaller than the minimum diameter of said firepot, of an annular support disc carried horizontally on said support flange, a circular tubular gas burner carried on said disc and having a diameter substantially equal to the inner diameter of said firepot, said burner being adapted to direct flames against the walls of said firepot, means for supplying gas to said burner, a vertically disposed cylindrical refractory wall disposed within said burner, said wall being supported at its lower end by said disc and extending the full height of said firepot, a plurality of refractory bars each having its lower end resting between said burner and said wall and having its upper end resting against the firepot wall, and lumps of refractory material filling the space between said wall and said bars.

JAMES N. ROSS.

REFERENCES CITED The following references are of record in the flle of this patent:

UNITED STATES PATENTS Number Name Date 442,863 Cox, Jr Dec. 16, 1890 470,679 Jenks Mar. 15, 1892 642,055 Ridgway Jan. 23, 1900 734,201. Thornton July 21, 1903 884,309 Biglar Apr. 7, 1908 964,902 Fall July 19, 1910 1,181,674 Korn May 2, 1916 1,217,551 Armor Feb. 27, 1917 1,578,210 Schrader Mar. 23,1926 1,667,133 Schrader Apr. 24, 1928 1,705,168 Young Mar. 12, 1929 1,799,902 Hoff Apr. 7, 1931 1,912,254 Galhoun May 30, 1933 1,936,950 Pauloo Nov. 28, 1933 1,946,791 Hagan Feb. 13, 1934 1,950,470 Bellamy Mar. 13, 1934 2,025,089 Bulger Dec. 24, 1935 2,210,551 Lengyel Aug. 6, 1940 FOREIGN PATENTS Number Country Date 149,539 Great Britain Aug. 19, 1920 333,269 Great Britain Aug. 11, 1930 

